Vehicles, such as motorcycles, are inherently unstable, and their use, particularly by inexperienced drivers, can be dangerous. Many factors such as excessive speed, road conditions, driver experience, poor equipment, and overtipping can contribute to accidents. The present invention relates to a device which can help prevent accidents which might otherwise occur when a vehicle is approaching a critical tilting angle.
The prior art discloses some tip sensors within a vehicle. U.S. Pat. No. 1,085,608 to Heath et al and U.S. Pat. No. 5,613,571 to Rank et al both disclose tip sensors within a vehicle for sensing a critical tilting angle, however the tip sensors do not sense an approaching critical angle nor do they provide any visible or auditory signals so that the driver may correct the vehicle's angle prior to reaching the critical angle. Instead, at the critical tilting angle, the prior tip sensors activate a circuit breaker to provide automatic shut-off of the machine. The driver must then restart the engine, which can be a nuisance. Thus, the driver may not be aware that a critical angle has been reached until the vehicle shuts off.
U.S. Pat. No. 4,200,168 to Moog discloses an apparatus for sensing the application of an overturning moment to the vehicle and for exerting a reaction torque on the vehicle to oppose such overturning moment by means of an inertia wheel. The apparatus described would greatly increase the size and weight of a vehicle, both of which are undesirable features when the space for performance related features on vehicles such as motorcycles is particularly limited. Again, no visible or audible warning is provided to the driver of an impending critical angle which allows a driver to correct a leaning position.
U.S. Pat. No. 4,145,682 to Cook and U.S. Pat. No. 4,682,145 to Brawner, Jr. disclose truck level sensors and indicators, but do not apply to vehicles such as motorcycles which are in driving mode, nor do they sense the proximity of a vehicle to the ground.
Thus, there is a need for a tilt angle sensor which can provide a visible or audible warning signal to a driver that the motorcycle is approaching a critical tilting angle so that the driver may correct the vehicle's tilting angle and prevent overturning of the vehicle. There is further a need for such a signal which can be used while driving and which allows the driver to continue driving after self-correction. There is further a need for such an apparatus which is inexpensive and which can be easily attached to an existing vehicle. There is a need for a device which can assist a motorcycle driver in avoiding unintended contact between the motorcycle and the ground.